Interactive Investor Review 2026: The Flat Fee That Wins Once You Pass £100,000
Score: 72/100. Rank 4 of 10. Verified 19 September 2026.
Cost 30% | Accounts 15% | Range 15% | Research 10% | App 10% | Cash 10% | Trust 10% |
5.0 | 8 | 10 | 9 | 7 | 6 | 8 |
Verdict in one paragraph
Two investors each have £400,000 in funds. One pays 0.35% at Hargreaves Lansdown, which after tiering is about £1,250 a year. The other pays Interactive Investor's £14.99 a month, £180 a year, and £1.49 per fund trade.
Over fifteen years that gap, compounded, is a five-figure sum. Interactive Investor is the platform that made flat fees mainstream, and after its February 2026 repricing into Core (£5.99 a month up to £100,000) and Plus (£14.99 above) it remains the cheapest full-service option for anyone with a large fund portfolio. It ranks fourth rather than higher because the flat fee is a poor deal under about £50,000, FX is 0.75%, and cash interest in the trading account is thin.
Who it is for
Fund investors with £100,000 or more in ISAs and SIPPs, and anyone who wants research depth without HL's percentage charge. Not for small portfolios, and no longer for US residents.
Interactive Investor Fees
Item | Charge |
Core plan | £5.99 a month, portfolio up to £100,000; includes ISA, SIPP and Trading Account |
Plus plan | £14.99 a month, no limit; one free trade a month (£3.99 credit); Junior ISAs and up to five free family accounts |
Premium plan | £39.99 a month; two free trades a month |
UK and US shares, ETFs, investment trusts | £3.99 per trade |
Funds | £3.99 Core; £1.49 Plus |
Other international shares | £9.99 Core; £7.99 Plus |
Regular investing | Free |
Dividend reinvestment | £0.99 |
FX | 0.75% (Plus: 0.25% above £50,000; Premium 0.25%) |
Transfers in and out | Free |
Interest on cash | Tiered by account and balance, 0.25% to 2.32% AER; ISA from 1.70% on the first £20,000 |
Our model: a £500,000 SIPP in ETFs costs £6,730 in true terms over 15 years, level with AJ Bell and below HL. A £100,000 ISA plus £500 a month in OEIC funds costs £6,435 over 20 years, against £19,436 at AJ Bell and £28,441 at HL. That is the flat-fee effect.
Where the break-even sits
Against AJ Bell's 0.25% fund fee, ii's £14.99 Plus plan is cheaper above roughly £72,000 in funds; Core at £5.99 is cheaper above roughly £29,000. Against HL's 0.35%, the crossovers are lower still. For ETF-only investors AJ Bell's £42 cap beats ii's flat fee at every size.
Accounts
Trading Account, Stocks and Shares ISA, Managed ISA, SIPP, Junior ISA (Plus and Premium), Joint Trading Account (£14.99 separately), and Managed Portfolios. Pension administration is included in the plan fee (£2.50 to £6 of it). No Lifetime ISA.
Investment range
One of the widest in the UK: funds, ETFs, investment trusts, bonds and gilts, UK and US shares at the standard £3.99 rate and a broad set of other international markets at £7.99 to £9.99. Multi-currency holdings in the SIPP and Trading Account.
Research and tools
Award-winning and genuinely useful: fund and trust research, Super 60 and ACE 40 rated lists, a share screener, portfolio analysis, and Quotestream real-time data as a paid add-on. Only IBKR and HL compare.
The catches
Small portfolios overpay. £71.88 a year on a £10,000 ISA is 0.72%.
FX at 0.75%. Fine for occasional US purchases, expensive for a heavy international investor.
Trading Account cash interest starts at 0.25% and is capped at 1.56% at the top tier.
Non-UK residents pay £5 a month extra, and US residents were exited from January 2026.
Plan-change rules are fiddly: changes within 14 days of the collection date apply next month.
US citizens and US persons
Interactive Investor wrote to clients it identified as US residents in late 2025 and restricted their Trading Accounts from 7 January 2026. Reports indicate US-connected clients also face restrictions on collective investments. Treat ii as closed to US persons.
Trust
Owned by abrdn plc, FCA-authorised, FSCS-covered, with around 29,000 Trustpilot reviews rated Excellent. It has absorbed TD Direct, Alliance Trust Savings, The Share Centre and EQi, so it has integration experience, and it has been consistently profitable.
Pros and cons
Pros: cheapest full-service option above £100,000 in funds; free regular investing; £1.49 fund dealing on Plus; huge range; excellent research; free family accounts. Cons: poor value under £50,000; 0.75% FX; weak cash interest on the Trading Account; closed to US persons; no LISA.
Frequently asked questions
Is Interactive Investor cheaper than Hargreaves Lansdown? For fund portfolios above about £25,000, yes, and the gap widens as the pot grows. For ETFs and shares in a small ISA, HL's and AJ Bell's caps can be cheaper than ii's flat fee.
What is the difference between ii Core and Plus?
Core is £5.99 a month for portfolios up to £100,000 with £3.99 dealing. Plus is £14.99 a month with no limit, £1.49 fund dealing, one free trade a month, Junior ISAs and free family accounts. You move to Plus automatically above £100,000.
Does Interactive Investor charge extra for a SIPP? No. Pension administration is included in the monthly plan fee.
Sources
Charges: https://www.ii.co.uk/our-charges
Cash interest rates (from 6 January 2026): https://www.ii.co.uk/investing-with-ii/cash-interest-rates
US-resident account closures: https://edale.co/interactive-investor-account-closure-for-us-residents-your-options-transfering/
US-connected client restrictions: https://cameronjamesusa.com/fidelity-pfic-restrictions-what-us-connected-us-persons-need-to-know/
Trustpilot: https://uk.trustpilot.com/review/ii.co.uk
Alpesh Patel is a fund manager and the founder of Campaign for a Million. This page is information and opinion, not a personal recommendation or financial advice. Capital is at risk. Tax treatment depends on individual circumstances and may change. Campaign for a Million receives no payment from any platform listed.
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